208 On the Cultivation of the Vine, 



indicate that the acids have conftant relations of quantity, 

 in the neutral falts they form, with different alkaline or earthy 

 bafes. So that, if the fulphuric acid, for example, exift in 

 greater proportion in the fulphate of potafh than in the ful- 

 phateoflime, the muriatic acid, with which it may make 

 an exchange of bafe, will be found in the fame ratio of 

 quantity in the muriate of lime and in the muriate of potafh; 

 a conclufion that would not agree with the proportions which 

 chemifts have often attributed to the component parts of the 

 different non-metallic falts. Guy ton has already made fe- 

 veral very juft and important reflections on this fubjeft, and 

 quotes the obfervations of Richter, with whofe work I am 

 not yet acquainted. (Annalcs de Cbimze, torn. xxv. p. 292.) 

 [ To be continued. ] 



XXXII. A Treatife on the Cultivation of the Vine> and the 

 Method of making Wines* 



[Continued from p. 151.] 



On the Clarification of Wines, 



2d, JJESIDES the operation of fulphuring wines, there 

 is another, no lefs efiential, called clarification. It confifls, 

 in the firft place, in drawing off the wine from the lees, 

 which requires certain precautions, and in then difengaging 

 it from all the principles fufpended or weakly difiblved in it ; 

 fo that nothing may be retained but the fpiritous and incor- 

 ruptible principles alone. Thefe operations are even per- 

 formed before that of fulphuring, which is only a continua- 

 tion of them. 



The firlt of thefe operations is called drawing off, tranf- 

 vafation, defecation. According to Ariftotle, this operation 

 ought to be often repeated : quoniam fwperveniente ajlatis ca- 

 lore folent faces jubverti, ac ita vina acefcere. 



In the different wine countries there are certain fixed pe- 

 riods of the year for this operation, eftablifhed, no doubt, on 

 the conftant and refpe&able observation of ages. At the 

 Hermitage, the wine is drawn off in March and September; 

 in Champagne, on the 13th of October, about the 15th of 

 February, and towards the end of March. 



Dry, cold weather is always chofen for this operation. It 

 is certain that it is then only that the wine is in a good con- 

 dition. Damp weather, and foutherly winds, always render 

 6 wine 



